1. In your theme, open Placement.info and add rules that say: don't render this and that shape when displaying the homepage:

<Placement><!-- Remove the page title and metadata from the homepage--><MatchPath="~/"><PlaceParts_RoutableTitle="-"/><PlaceParts_Common_Metadata="-"/></Match></Placement>

(Note that with Orchard 1.4, the Routable module has been replaced with Autoroute and Title, which will probably generate differently named shapes. Use the Shape Tracer to find the shapes that you whish to remove from the homepage).